This invention relates to a vise to hold a workpiece, and more particularly to an improved vise which is provided with a jaw member having a plurality of jaw faces readily selectable so as to achieve a best advantageous grip of the object workpiece.
A conventional vise, large or small, has a couple of jaw plates, one fixed to the stationary main body and the other to the adjustible body of the vise, and furthermore, said jaw have, in general, notched or serrated faces, which are often proved to be inefficient to insure a secure and positive grip for certain workpieces.
For example, with workpiece that is round, globular, or cylindrical in shape, a conventional vise having fixed and notched jaw faces holds such a workpiece at no more than two linear points or at best along two parallel lines. Therefore, the resultant gripping effect is insufficient for such a workpiece to stand the operation force and consequently, many inconveniences are caused, such as drill failing, surface scratching and even damaging of the piece upon compressing in excess to prevent the piece from slipping; sometimes it becomes a near accident as the workpiece springs wild from the jaws by the operation impact.
It is therefore a general object of the present invention to provide an improved vise with a replaceably mounted jaw member having a plurality of jaw faces in different shapes which can be rotated so as to place selectively into the grip position a jaw face most suitable to insure a slip-proof grip of the particular workpiece without damage.
It is still more specific object of this invention to provide an improved vise which has, as the stationary jaw and/or the adjustible jaw, a replaceably mounted rotatable jaw member having at least two jaw faces of different shapes so that an adequate jaw face can be readily selected at the stationary side and/or the adjustible side of the vise to insure a perfect grip of the workpiece therebetween.
A further object of this invention is to provide an improved vise in which the adjustible jaw body includes as a jaw unit at least two forks, each having a jaw plate at the outermost end thereof, and is adapted to rotate so as to place any of its jaw plates into the adjustible grip position.